# Quiz3 - the years 2000 and 2007 is football shaped The...

This preview shows page 1. Sign up to view the full content.

STAT 21 SP 09 QUIZ 3 NAME: SID: 1. A group of children has their weights measured at age 10 and 16; the scatter diagram is football shaped. The average weight for the children at age 10 is 85 pounds, and 97 pounds at the age 16. The SD is 15 pounds for both cases. The correlation between the two variables is 0.8. According to the regression method, predict the weight of a 16-year-old child who weighed 90 pounds at the age of 10. 2. Children from 400 two-child families are given the WISC test on their reading skills. The average score of the first-born children is 29 and the SD is 10. The average score of the second-borns is 28 and the SD is 10. The scatter diagram is football shaped. The correlation between the two variables is 0.70. Of all the first-borns who score 27 in the test, about what percentage have a sibling scoring more than 29? 3. The scatter diagram of the daily measured quantity of precipitation in London for
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: the years 2000 and 2007 is football shaped. The correlation is positive but not equal to 1. One particular day is on the 31st percentile of daily quantity of precipitation in 2000 and on the 31st percentile of daily quantity of precipitation in 2007. This day’s precipitation in 2007 (i) is equal to (ii) is less than (iii) is greater than (iv) cannot be compared to the average precipitation level in 2007 of all the days on the 31st percentile in 2000. 4. Find the equation for the regression line for the following data set about weekly usage of vegetable oil and weight for a group of 5. Sample 1 2 3 4 5 Number of vegetable-oil-cooked meals per week 14 16 6 11 12 Weight (pounds) 108 110 145 121 118 If one of them eats one more meal cooked by vegetable oil every week, will his weight drop according to the regression line? If not, what does the slope mean? 1...
View Full Document

## This note was uploaded on 07/08/2010 for the course STATS 21 taught by Professor Ibser during the Spring '09 term at Berkeley.

Ask a homework question - tutors are online